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-rw-r--r--posix/execvp.c112
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diff --git a/posix/execvp.c b/posix/execvp.c
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+/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <ansidecl.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <limits.h>
+#include <sys/types.h>
+
+#ifndef HAVE_GNU_LD
+#define __environ environ
+#endif
+
+/* Execute FILE, searching in the `PATH' environment variable if it contains
+ no slashes, with arguments ARGV and environment from `environ'. */
+int
+DEFUN(execvp, (file, argv), CONST char *file AND char *CONST argv[])
+{
+ if (strchr (file, '/') == NULL)
+ {
+ char *path, *p;
+ struct stat st;
+ size_t len;
+ uid_t uid;
+ gid_t gid;
+ int ngroups;
+ gid_t groups[NGROUPS_MAX];
+ char *name;
+
+ path = getenv ("PATH");
+ if (path == NULL)
+ {
+ /* There is no `PATH' in the environment.
+ The default search path is the current directory
+ followed by the path `confstr' returns for `_CS_PATH'. */
+ len = confstr (_CS_PATH, (char *) NULL, 0);
+ path = (char *) __alloca (1 + len);
+ path[0] = ':';
+ (void) confstr (_CS_PATH, path + 1, len);
+ }
+
+ len = strlen (file) + 1;
+ name = __alloca (strlen (path) + len);
+ uid = geteuid ();
+ gid = getegid ();
+ ngroups = getgroups (sizeof (groups) / sizeof (groups[0]), groups);
+ p = path;
+ do
+ {
+ path = p;
+ p = strchr (path, ':');
+ if (p == NULL)
+ p = strchr (path, '\0');
+
+ if (p == path)
+ /* Two adjacent colons, or a colon at the beginning or the end
+ of `PATH' means to search the current directory. */
+ (void) memcpy (name, file, len);
+ else
+ {
+ /* Construct the pathname to try. */
+ (void) memcpy (name, path, p - path);
+ name[p - path] = '/';
+ (void) memcpy (&name[(p - path) + 1], file, len);
+ }
+ if (stat (name, &st) == 0 && S_ISREG (st.st_mode))
+ {
+ int bit = S_IXOTH;
+ if (st.st_uid == uid)
+ bit = S_IXUSR;
+ else if (st.st_gid == gid)
+ bit = S_IXGRP;
+ else
+ {
+ register int i;
+ for (i = 0; i < ngroups; ++i)
+ if (st.st_gid == groups[i])
+ {
+ bit = S_IXGRP;
+ break;
+ }
+ }
+ if (st.st_mode & bit)
+ {
+ file = name;
+ break;
+ }
+ }
+ }
+ while (*p++ != '\0');
+ }
+
+ return __execve (file, argv, __environ);
+}